There isn't much doubt that all future purchasing and banking will done with a smart phone. New tech being tested like no pin number or signature payments are just "fill ins" until the final technology is perfected.
An old idea that has fallen by the wayside is having a picture of a card holder on the card itself. Just why this concept was dropped is unknown. The only card now with your photo is your driving licence.
Paying with a finger print is also something thought about, tested but never marketed. Retail at the moment is a mishmash of different methods of payment including the old fashioned cash payment. Older people still like to draw cash from an ATM. They like the idea of having cash on them so they can pay immediately. Immediacy will be even quicker using a smart phone.
Bendigo Bank has developed a system where a phone app generates a random code to finalize a transaction. They have been using such a system in the UK for many years now.
Eventually, a phone held against one's skin will take a measure of blood flowing through. A partial DNA reading will be taken which will verify that the phone owner and bank account holder is indeed the correct person. Much of this is possible with existing technology.
Technology by Ty Buchanan